基于碳纳米管和铁氰酸镍纳米颗粒协同作用的葡萄糖生物传感器

将制备的铁氰酸镍纳米颗粒(NiNP)与多壁碳纳米管(CNT)混合, 分散于壳聚糖溶液中, 形成一种新的纳米复合成分(NiNP-CNT-CHIT), 将其修饰在玻碳电极表面. 新复合膜体现了NiNP和CNT之间的协同作用, 由于CNT的良好的传递电子性能, 促使NiNP催化氧化还原能力有了较大的提高. 此NiNP-CNT-CHIT复合膜修饰的玻碳电极在较低电位下对过氧化氢具有良好的电催化性能, 与NiNP-CHIT膜比较, 测定H₂O₂的灵敏度增大了50倍. 通过戊二醛在电极表面固定葡萄糖氧化酶制备了一种新的葡萄糖传感器. 该传感器在－0.2 V下对葡萄糖的线性范围为0.05～10 mmol/L, 检测下限为10 μmol/L.

Glucose Biosensor Based on the Synergy between Carbon Nanotubes and Nickel Hexacyanoferrate Nanoparticles

Nickel hexacyanoferrate nanoparticles (NiNP) can be easily prepared by mixing hexacyanoferrate and nickel chloride solution at room temperature. The nanoparticles were solubilized in aqueous solution of a biopolymer chitosan (CHIT). With the introduction of carbon nanotubes (CNT), the NiNP-CNT- CHIT system formed shows synergy between CNT and NiNP with the significant improvement of redox activity of NiNP due to the excellent electron-transfer ability of CNT. The NiNP-CNT-CHIT film modified glassy carbon electrode allows low potential detection of hydrogen peroxide with high sensitivity and fast response time. In particular, with the introduction of CNT, it amplified the H₂O₂ sensitivity by ～50 times compared to film of NiNP-CHIT. With the immobilization of glucose oxidase onto the electrode surface using glutaric dialdehyde, a biosensor that responds sensitively to glucose has been constructed. In pH 6.98 phosphate buffer, interference free determination of glucose has been realized at －0.2 V vs. SCE with a linear range from 0.05 to 10 mmol/L and response time ＜10 s. The detection limit was 10 μmol/L glucose (S/N＝3).